SonicWALL 5.8.1 Manuale Utente

L2 Bridge Mode employs a secure learning bridge architecture, enabling it to pass and 
inspect traffic types that cannot be handled by many other methods of transparent security 
appliance integration. Using L2 Bridge Mode, a SonicWALL security appliance can be non-
disruptively added to any Ethernet network to provide in-line deep-packet inspection for all 
traversing IPv4 TCP and UDP traffic. Unlike other transparent solutions, L2 Bridge Mode 
can pass all traffic types, including IEEE 802.1Q VLANs, Spanning Tree Protocol, 
multicast, broadcast, and IPv6, ensuring that all network communications will continue 
uninterrupted. 

L2 Bridge Mode provides an ideal solution for networks that already have an existing 
firewall, and do not have immediate plans to replace their existing firewall but wish to add 
the security of SonicWALL Unified Threat Management (UTM) deep-packet inspection, 
such as Intrusion Prevention Services, Gateway Anti-Virus, and Gateway Anti Spyware. 

The following feature enhancements are included in SonicOS Enhanced 5.0 and higher:

Enhanced Packet Capture - Enhanced Packet Capture contains improvements in both 
functionality and flexibility, including the following:

Capture control mechanism with improved granularity for custom filtering

Display filter settings independent from capture filter settings

Packet status indicating dropped, forwarded, generated, or consumed

Three-window output in the user interface that provides the packet list, decoded output 
of selected packet, and hexadecimal dump of selected packet

Export capabilities that include text, HTML, hex dump, and CAP file format

Automatic buffer export to FTP server when full

Bidirectional packet capture based on IP address and port

Configurable wrap-around of capture buffer when full

User Authentication - There are a number of enhancements to user authentication, 
including optional case-sensitive user names, optional enforcement of unique login names, 
support for MSCHAP version 2, and support for VPN and L2TP clients changing expired 
passwords (when that is supported by the back-end authentication server and protocols 
used). Note that for this purpose there is a new setting on the VPN > Advanced page to 
cause RADIUS to be used in MSCHAP mode when authenticating VPN client users.

IP Helper Scalability - The IP Helper architecture is enhanced to support large networks. 
Improvements include changes to DHCP relay and Net-BIOS functionality. DHCP relay 
over VPN is now fully integrated.

Diagnostics Page Tool Tips - Self-documenting mouseover descriptions are provided for 
diagnostic controls in the graphical user interface.

BWM Rate Limiting - The Bandwidth Management feature is enhanced to provide rate 
limiting functionality. You can now create traffic policies that specify maximum rates for 
Layer 2, 3, or 4 network traffic. This enables bandwidth management in cases where the 
primary WAN link fails over to a secondary connection that cannot handle as much traffic.

DHCP Client Reboot Behavior Control - In SonicOS Enhanced 5.0 and higher, you can 
configure the WAN DHCP client to perform a DHCP RENEW or a DHCP DISCOVERY 
query when attempting to obtain a lease. The previous behavior was to always perform a 
RENEW, which caused lease failures on some networks, particularly certain cable modem 
service providers. The new behavior it to perform a DISCOVERY, but it is configurable. A 
checkbox has been added to the Network > Interfaces > WAN >DHCP Client page:

Enabled: when the appliance reboots, the DHCP client performs a DHCP RENEW 
query.